In an apparatus of the type known from U.S. Pat. No. 5,167,360, Ritter, to which EP-389 465 corresponds, the wire supply device is disposed on a base frame and, separated from it, a device for forming and shaping a wire receiving duct in the insulating body, which is linearly displaceable and pivotable synchronously with the wire supply device. A plurality of forming and shaping devices, placed on top of each other in a vertical direction, can be provided. The known device has the disadvantage that the forming and shaping device is disposed separated from the wire supply device and must therefore be separately triggered and displaced, and that the distance between the forming and shaping device and the wire supply device is fixedly preset.